This invention relates to improvements in the action for keyboard instruments of the harpsichord or plectrum piano type wherein the strings or vibratable elements therein are set in motion by a pick or plectrum. In particular, the invention relates to an improved means of providing such instruments with the "piano-forte" or soft-loud effect, that is, the effect wherein the player can vary the loudness of individual tones by applying more or less force at the keyboard. In a previous disclosure (U.S. Pat. No. 4,099,440) I described an action which utilized the resistance of a pneumatic piston to provide such an effect. In the present disclosure I describe a new and improved means of implementing such pneumatic actions which eliminates the noise previously associated therewith and which allows a more pleasing appearance of the instrument by eliminating that part of the action suspended below the keyboard. Furthermore, my new action utilizes a direct connecting rod between the pneumatic piston and the plectrum and the rod is constructed so as to also serve as part of the repeat valve, thus simplifying the previous design.